TY - CHAP A1 - Fischer, Thomas A1 - Veste, Maik A1 - Eisele, Andreas A1 - Bens, Oliver A1 - Spyra, Wolfgang A1 - Hüttl, Reinhard F. T1 - High resolution mapping of Normalized Difference Vegetation Indices (NDVI) of biological soil crusts T2 - EGU General Assembly 2012, held 22-27 April, 2012 in Vienna Y1 - 2012 N1 - EGU2012-7052 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Mantovani, Dario A1 - Veste, Maik A1 - Freese, Dirk T1 - Biomass production and water use of Black Locust (Robinia pseudoacacia L.) for short-rotation plantation T2 - EGU General Assembly 2012, held 22-27 April, 2012 in Vienna Y1 - 2012 N1 - EGU2012-8719 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - CHAP A1 - Spröte, Roland A1 - Veste, Maik A1 - Fischer, Thomas A1 - Lange, Philipp A1 - Bens, Oliver A1 - Raab, Thomas A1 - Hüttl, Reinhard F. T1 - Wie beeinflussen Kiefern (Pinus sylvestris L.) die Entwicklung der Benetzungshemmung auf Sandböden? T2 - Böden verstehen - Böden nutzen - Böden fit machen, Jahrestagung der Deutschen Bodenkundlichen Gesellschaft, 3. - 9. September 2011 Y1 - 2011 UR - http://eprints.dbges.de/768/ ER - TY - CHAP A1 - Spröte, Roland A1 - Veste, Maik A1 - Fischer, Thomas A1 - Lange, Philipp A1 - Bens, Oliver A1 - Raab, Thomas A1 - Hüttl, Reinhard F. T1 - Development of biologicalsoil crusts in initial ecosystems in Lusatia, Germany T2 - DBG Jahrestagung 2009 Bonn "Böden - eine endliche Ressource", 05.-13.09.2009, Bonn Y1 - 2009 UR - http://eprints.dbges.de/178/ ER - TY - GEN A1 - Schaaf, Wolfgang A1 - Gerwin, Werner A1 - Biemelt, Detlef A1 - Veste, Maik A1 - Fischer, A. T1 - Monitoring of Soil-Plant-Atmosphere patterns and processes in an artificial catchment T2 - EGU General Assembly 2009, Vienna, Austria, 19 – 24 April 2009 Y1 - 2009 N1 - EGU2009-4364 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - GEN A1 - Veste, Maik A1 - Dominik, R. A1 - Dimitrov, M. A1 - Fischer, A. A1 - Gerwin, Werner A1 - Schaaf, Wolfgang ED - Stadler, Jutta ED - Schöppe, Felix ED - Frenzel, Mark T1 - Novel drone-based system for ecosystem monitoring - application, analysis and interpretation T2 - EURECO-GFOE 2008, Proceedings Y1 - 2008 SN - 978-3-00-025522-9 SP - S. 809 PB - Gesellschaft für Ökologie CY - Berlin ER - TY - GEN A1 - Fischer, Thomas A1 - Veste, Maik A1 - Eisele, Andreas A1 - Bens, Oliver A1 - Spyra, Wolfgang A1 - Hüttl, Reinhard F. T1 - Small Scale Spatial Heterogeneity of Normalized Difference Vegetation Indices (NDVI) and Hot Spots of Photosynthesis in Biological Soil Crusts T2 - Flora N2 - Normalized Difference Vegetation Indices (NDVIs) are typically determined using satellite or airborne remote sensing, or field portable spectrometers, which give an averaged signal on centimetre to metre scale plots. Biological soil crust (BSC) patches may have smaller sizes, and ecophysiological, hydrological as well as pedological processes may be heterogeneously distributed within this level of resolution. A ground-based NDVI imaging procedure using low-cost equipment (Olympus Camedia 5000z digital camera equipped with a Hoya R72 infrared filter) was developed in this study to fill this gap at the level of field research, where carrying costly and bulky equipment to remote locations is often the limiting factor for data collection. Method principle and field data are presented, and the field experiment was deepened comparing NDVI measurements and CO2 turnover of soil crust samples in the laboratory, backing the reliability of the approach. A commercially available colour rendition chart with known red (600–700 nm) and NIR (800–900 nm) reflectances was placed into each scene and used for calibration purposes on a per-image basis. Generation of NDVI images involved (i) determination of red and NIR reflectances from the pixel values of the red and NIR channels, respectively, and (ii) calculation and imaging of the NDVI, where NDVI values of −1 to +1 were mapped to grey values of 0 to 255. The correlation between NDVI values retrieved from these images and NDVI values determined using field spectrometry was close (r2 = 0.91), the 95% confidence interval amounted to 0.10 NDVI units. The pixel resolution was 0.8 mm in the field and 0.2 mm in the laboratory, but can still be improved significantly with closer distance to the crust or with higher camera resolution. NDVI values obtained using the new method were related to the net CO2 uptake of BSCs, where both slope and correlation coefficient of the respective regression function conformed with literature data. Geostatistical analysis revealed that both spatial variability of net CO2 uptake as well as size of individual hot spots of this parameter increased with crust development. The latter never exceeded 4 mm in the investigated crusts, which points to the necessity of high resolution imaging for linking remote sensing with ecophysiology. Perspectively, the new method could be used for field monitoring of both biological soil crusts and vascular vegetation. Y1 - 2012 U6 - https://doi.org/10.1016/j.flora.2012.01.001 VL - 207 IS - 3 SP - 159 EP - 167 ER - TY - GEN A1 - Kleefeld, Andreas A1 - Gypser, Stella A1 - Herppich, Werner B. A1 - Bader, Georg A1 - Veste, Maik T1 - Identification of spatial pattern of photosynthesis hotspots in moss- and lichen-dominated biological soil crusts by combining chlorophyll fluorescence imaging and multispectral BNDVI images T2 - Pedobiologia N2 - Although biological soil crusts can be found in open landscapes worldwide, their species composition depends on soil properties such as texture and pH, on microclimate, and their respective developmental stage. In addition, local variations in water holding capacity and/or chemical properties of soils influence the formation of spatial patterns and different types of biocrusts on the landscape level. For the evaluation of biocrusts functions and their impact on soil carbon pools, the analysis of the interrelationship between photosynthetic activity and the variations of spatial distribution pattern and types of biocrust is indispensable. For this purpose, an image processing approach was applied that combined chlorophyll fluorescence analyses and multispectral BNDVI to comprehensively characterize the spatial patterns of photosynthetic hotspots in biological soil crusts. For image analysis, five biological soil crust samples with different ratios of substrate, mosses and lichens were collected on an inland dune system in Lieberose, dominated by the moss Polytrichum piliferum, and the lichens Cladonia fimbriata and C. coccifera. RGB-images of the biocrusts were taken with a standard consumer camera Nikon 5200, BNDVI images with a modified Canon S110 NIR camera and chlorophyll fluorescence images with a modular open FluorCAM FC 800-O/1010, respectively. BNDVI and Fv/Fm were nearly in the same range for all biocrust samples related to the total surface area. Although mosses showed higher BNDVI than lichens within the separate biocrust samples. F0 and Fm increased with species coverage and with advancing biocrust development. Overlapping of BNDVI with F0 and Fm images showed that not all crustal organisms contribute to BNDVI and chlorophyll fluorescence. The overlapping areas of BNDVI and F0 ranged between 13% and 29%, that of BNDVI and Fm between 17% and 47%. Matching of RGB, BNDVI and CFI allows visualizing spatial pattern with high or low photosynthesis in biocrusts. Y1 - 2018 U6 - https://doi.org/10.1016/j.pedobi.2018.04.001 SN - 1873-1511 VL - 68 SP - 1 EP - 11 ER - TY - GEN A1 - Veste, Maik A1 - Herppich, Werner B. T1 - Comparative ecophysiology of the leaf-succulents Augea capensis (C3) and Malephora purpureo-crocea (CAM) in the Knersvlakte, Succulent Karoo, South Africa T2 - Flora N2 - The generally accepted assumption that CAM is an important adaptation to the drought conditions in arid deserts is mainly based on studies in controlled environments comparing the respective photosynthetic pathways in plants of different morphology. Comparative long-term field studies on the ecophysiology of C3- and CAM succulents co-occurring in the same desert habitat are too rare to satisfactorily answer the old question whether the metabolic pathway or the succulence is more important to guarantee survival in such a harsh habitat. Thus, relevant ecophysiological parameters were repeatedly monitored on plants of the leaf succulents Augea capensis (C3) and Malephora purpureo-crocea (CAM), which commonly dominate a habitat in the Knersvlakte, Namaqualand, South Africa. Under identical conditions in the same habitat, carbon gain of the C3 species was higher than that of the CAM plant, but their WUE lower and maximum photosynthetic activity nearly the same. In M. purpureo-crocea, irrigation induced rapid whole day stomatal opening at drastically increased daytime but decreased night-time CO2-uptake, while respective responses of the C3 species were delayed. These different response dynamics were due to different rooting depth, root morphology and water acquisition strategy of the flat rooting CAM and the deep-rooting C3 species. This, however, may not explain the highly similar growth success. Anyway, the results verify that CAM provides no advantage over C3 for long-term survival in the same desert environment in morphologically similar succulents. KW - Mode of photosynthesis Y1 - 2021 U6 - https://doi.org/10.1016/j.flora.2021.151807 SN - 1618-0585 SN - 0367-2530 VL - 278 ER - TY - GEN A1 - Griebenow, Stian A1 - Makunga, Nokwanda P. A1 - Privett, Sean A1 - Strauss, Paula A1 - Veste, Maik A1 - Kleinert, Aleysia A1 - Valentine, Alexander J. T1 - Soil pH influences the organic acid metabolism and exudation in cluster roots of protea species from the Mediterranean-type fynbos ecosystem, Western Cape, South Africa T2 - Rhizosphere N2 - In nutrient-poor ecosystems, certain plant families have evolved specific adaptations for phosphate acquisition, namely cluster roots or proteoid roots. Cluster rooted species have a unique suite of adaptations that enable them to survive in nutrient poor ecosystems, such as the Fynbos biome of South Africa. The Fynbos biome has heterogeneous soils which caused radiation of varying soil pH within small localised areas. Previous studies on cluster rooted species ignored the possibility that cluster root functioning may differ at varying soil pH levels and soil types. Therefore, two native Fynbos protea species, Protea cynaroides (L.) L. and Protea obtusifolia H.Buek ex Meisn. were compared to assess the impact of different soil pH levels on organic acid metabolism and exudation in cluster rooted species. Our results show that cluster roots of the acidic-soil grown P. cynaroides is more effective and more efficient than that of the alkaline-soil grown P. obtusifolia. Our findings indicate that the mechanisms for P acquisition vary greatly, depending on substrate and plant organ type. This suggests that the metabolism of each species is adapted to specific soil pH and that these species have evolutionary adapted their P acquisition mechanisms for these extreme soils. The limited nutrient availability and variation in soil pH South African soils has led to various localised adaptations for cluster rooted species. KW - Phosphorus KW - Nutrient poor ecosystems KW - Root research Y1 - 2022 UR - https://www.sciencedirect.com/science/article/pii/S2452219822000167 U6 - https://doi.org/10.1016/j.rhisph.2022.100486 VL - Vol. 21 ER -